> I have heard a lot about a method of jointing a fiberglass deck to a
> fiberglass hull by using "H" channel. Can anyone tell me a
> little bit more about this method and a source for H channel(to purchase)?

Last year, I built a double from a kit sold by Nomad Kayaks, and it used the H channel method of joining the top to the bottom. You fit the deck to the hull with the H channel between and then apply fiberglass tape along the inside seam to seal it and keep it in place. West Marine sells other material like H-channel, but I haven't found the H-channel in their catalog. They might have it anyway. If not, you could send email to Nomad Kayaks and ask them where they get it.